He estimated how many species of insects lived on each plant species in England, and then extrapolated that figure across the whole planet. âIf we say 400,000, we shall, perhaps, not be very wide of the truth,â he wrote. Today, scientists know the Westwood figure is far too low.
Symptoms: A chronic dry cough that's worse at night, disturbing sleep, and sometimes with wheezing and shortness of breath. Causes: An irritating night cough is often the first sign of asthma, especially in children, but you can develop it at any age. It's also a sign asthma is worsening or not being well controlled.
The chances of experiencing asthma symptoms are higher during sleep. Nocturnal wheezing, cough, and trouble breathing are common yet potentially dangerous. Many doctors often underestimate nocturnal asthma or nighttime asthma. Studies show that most deaths related to asthma symptoms such as wheezing occur at night.